/* \$Id: jquery.numeric.js 313 2011-11-18 04:09:24Z bobcat $ */
/**
 * @license
 * Copyright (c) 2006/2007 Sam Collett (http://www.texotela.co.uk)
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 * 
 * Version 1.0
 * Demo: http://www.texotela.co.uk/code/jquery/numeric/
 *
 * $LastChangedDate: 2007-05-29 11:31:36 +0100 (Tue, 29 May 2007) $
 * $Rev: 2005 $
 */
 
/**
 * Allows only valid characters to be entered into input boxes.
 * Note: does not validate that the final text is a valid number
 * (that could be done by another script, or server-side)
 *
 * @name     numeric
 * @param    decimal      Decimal separator (e.g. '.' or ',' - default is '.')
 * @param    callback     A function that runs if the number is not valid (fires onblur)
 * @author   Sam Collett (http://www.texotela.co.uk)
 * @example  $(".numeric").numeric();
 * @example  $(".numeric").numeric(",");
 * @example  $(".numeric").numeric(null, callback);
 *
 */
jQuery.fn.numeric = function(decimal, callback)
{
  decimal = decimal || ".";
  callback = typeof callback == "function" ? callback : function(){};
  this.keypress(
    function(e)
    {
      var key = e.charCode ? e.charCode : e.keyCode ? e.keyCode : 0;
      // allow enter/return key (only when in an input box)
      if(key == 13 && this.nodeName.toLowerCase() == "input")
      {
        return true;
      }
      else if(key == 13)
      {
        return false;
      }
      var allow = false;
      // allow Ctrl+A
      if((e.ctrlKey && key == 97 /* firefox */) || (e.ctrlKey && key == 65) /* opera */) return true;
      // allow Ctrl+X (cut)
      if((e.ctrlKey && key == 120 /* firefox */) || (e.ctrlKey && key == 88) /* opera */) return true;
      // allow Ctrl+C (copy)
      if((e.ctrlKey && key == 99 /* firefox */) || (e.ctrlKey && key == 67) /* opera */) return true;
      // allow Ctrl+Z (undo)
      if((e.ctrlKey && key == 122 /* firefox */) || (e.ctrlKey && key == 90) /* opera */) return true;
      // allow or deny Ctrl+V (paste), Shift+Ins
      if((e.ctrlKey && key == 118 /* firefox */) || (e.ctrlKey && key == 86) /* opera */
      || (e.shiftKey && key == 45)) return true;
      // if a number was not pressed
      if(key < 48 || key > 57)
      {
        /* '-' only allowed at start */
        if(key == 45 && this.value.length == 0) return false;
        /* only one decimal separator allowed */
        if(key == decimal.charCodeAt(0) && this.value.indexOf(decimal) != -1)
        {
          allow = false;
        }
        // check for other keys that have special purposes
        if(
          key != 8 /* backspace */ &&
          key != 9 /* tab */ &&
          key != 13 /* enter */ &&
          key != 35 /* end */ &&
          key != 36 /* home */ &&
          key != 37 /* left */ &&
          key != 39 /* right */ &&
          key != 46 /* del */
        )
        {
          allow = false;
        }
        else
        {
          // for detecting special keys (listed above)
          // IE does not support 'charCode' and ignores them in keypress anyway
          if(typeof e.charCode != "undefined")
          {
            // special keys have 'keyCode' and 'which' the same (e.g. backspace)
            if(e.keyCode == e.which && e.which != 0)
            {
              allow = true;
            }
            // or keyCode != 0 and 'charCode'/'which' = 0
            else if(e.keyCode != 0 && e.charCode == 0 && e.which == 0)
            {
              allow = true;
            }
          }
        }
        // if key pressed is the decimal and it is not already in the field
        if(key == decimal.charCodeAt(0) && this.value.indexOf(decimal) == -1)
        {
          allow = false;
        }
      }
      else
      {
        allow = true;
      }
      return allow;
    }
  )
  .blur(
    function()
    {
      var val = jQuery(this).val();
      if(val != "")
      {
        var re = new RegExp("^\\d+$|\\d*" + decimal + "\\d+");
        if(!re.exec(val))
        {
          callback.apply(this);
        }
      }
    }
  );
  return this;
}